The present invention relates to an air nozzle device for a vehicle comprising a housing defining an interior volume and having an air inlet at one side, an air discharge opening at a second side and an air flow channel through the housing for transporting a flow of air between the air inlet and the air discharge opening, the device further comprising an air flow regulator mechanism comprising a rod member comprising a rack, at least one flap member comprising a pinion, and an assembly guide mechanism arranged to be moveable between an assembly position and a non-assembly position, wherein the rack and pinion is arranged to, in an assembled state, interact to rotate the at least one flap member about an axis between an open and a closed position to regulate the flow of air in the air flow channel, the assembly guide mechanism is, in the assembly position, arranged to interact with the at least one flap member and the rod member to assemble the rack and pinion, and the assembly guide mechanism is, in the non-assembly position, arranged to obstruct the assembly of the rack and pinion.